IBM System storage DS6000 Series, Redbooks

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Appendix A. Operating systems specifics
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The management of MPIO devices is described in the “Managing MPIO-Capable Devices”
section of the System Management Guide: Operating System and Devices for AIX 5L:
http://publib16.boulder.ibm.com/pseries/en_US/aixbman/baseadmn/manage_mpio.htm
Determine the installed SDDPCM level
You use the same command as for SDD, lslpp -l "*sdd*" , to determine the installed level
of SDDPCM. It will also tell you whether you have SDD or SDDPCM installed.
SDDPCM software provides useful commands such as:
򐂰 pcmpath query device to check the configuration status of the devices
򐂰 pcmpath query adapter
to display information about adapters
򐂰 pcmpath query essmap to display each device, path, location, and attributes
Useful MPIO commands
The lspath command displays the operational status for the paths to the devices, as shown in
Example A-8. It can also be used to read the attributes of a given path to an MPIO-capable
device.
Example: A-8 lspath command result
{part1:root}/ -> lspath |pg
Enabled hdisk0 scsi0
Enabled hdisk1 scsi0
Enabled hdisk2 scsi0
Enabled hdisk3 scsi7
Enabled hdisk4 scsi7
...
Missing hdisk9 fscsi0
Missing hdisk10 fscsi0
Missing hdisk11 fscsi0
Missing hdisk12 fscsi0
Missing hdisk13 fscsi0
...
Enabled hdisk96 fscsi2
Enabled hdisk97 fscsi6
Enabled hdisk98 fscsi6
Enabled hdisk99 fscsi6
Enabled hdisk100 fscsi6
The chpath command is used to perform change operations on a specific path. It can either
change the operational status or tunable attributes associated with a path. It cannot perform
both types of operations in a single invocation.
The rmpath command unconfigures or undefines, or both, one or more paths to a target
device. It is not possible to unconfigure (undefine) the last path to a target device using the
rmpath command. The only way to do this is to unconfigure the device itself (for example, use
the rmdev command).
Refer to the man pages of the MPIO commands for more information.
Restriction: A point worth considering when deciding between SDD and MPIO is, that the
IBM TotalStorage SAN Volume Controller does not support MPIO at this time. For updated
information refer to:
http://www-03.ibm.com/servers/storage/support/software/sanvc/installing.html